A biological reactive flame retardant for flame retardant modification of cotton fabric

A novel, high-efficiency, bio-based flame retardant ammonium salt of arginine hexamethylenephosphonic acid (AAHMPA) for cotton fabric was synthesized and grafted onto the cotton fabric by P–O–C and C–O–C covalent bonds. The flame retardancy and durability of treated cotton were improved obviously. The limiting oxygen index (LOI) value of 35 wt% AAHMPA-treated cotton reached 45.1%, and after 50 laundering cycles (LCs), the LOI value remained at 28.6%. The cone calorimeter, thermogravimetric and vertical flammability test indicated that treated cotton decomposed into phosphoric acid or polyphosphoric acid during combustion, which promoted the thermal degradation and charring of cotton fabrics and hindered the spread of flames. The mechanical properties of treated cotton fibers were slightly reduced. These results confirmed that AAHMPA treated cotton obtained excellent flame retardancy and high durability. • Flame-retardant cotton fabric was prepared by surface modification. • The treated cotton fabric has excellently durable flame retardant. • The flame retardant can form P–O–C and C–O–C covalent bonds with cotton fibers. • The raw materials of flame retardant are naturally-abundant. • Flame retardants will not produce harmful substances during use.